Fluoride as pollutant in air, water and its impacts on plants

Fluoride as pollutant in air, water and its impacts on plants

1. Fluoride As Pollutant In Air, Water And Soil And Its Impacts On Plants Jannat Iftikhar Roll # B11-16 8 th Semester 1 Course Title: Agriculture And Environmental Pollution Module Code Bot- 437

2. History Of Fluoride Pollution 2

3. History Of Fluoride Pollution 3

4. Properties Of Fluorine Not present in free elemental state Most reactive Most electronegative Fluorine can form both covalent and electrovalent bonds Fluorine forms very strong bonds with carbon They are resistant to biological and chemical attack 4

5. 5 Sources of Fluoride in Atmosphere Natural sources Anthropogenic sources

6. 6 Natural Sources Forest fires Volcanoes

7. 7 7 Minerals According to Fleischer (1953), fluoride accounts for 0.032% of the earth crust Major minerals are Fluorite (CaF 2 ), Fluorapatite (Ca 10 F 2 (PO 4 ) 6 ) and Caryolite (Na 3 AlF 6 ). Identified world reserves of fluoride are around 500 million t and annual mine production is in excess of 4.5 million t. 13 th (Smith and Hodge, 1979) or 17 th (Fleischer, 1953) most abundant element in the earth crust.

8. 8 Natural waters Depends on the geology, chemistry, physical characteristics and climate of the area. If water is not in contact with high fluoride minerals the range of concentration is from 0.01 to 0.4mg/L. The highest fluoride concentration tend to occur in arid regions. The Rift Valley of East Africa has the highest concentration on record, upto 300 mg/l

9. 9 Volcanoes, Forest Fires And Oceans 600 known, active volcanoes Halmer et al. (2002) have estimated the global annual emmision of HF from valcanoes are being from 7000 to 8000 kt. T he total atmospheric inorganic fluoride under 0.1 and mostly <0.05µg/m 3 . ( WHO , 2002 ) HF main form, others are; SiF , ammonium flourosilicates , sodium flourosilicates , potasium fourosilictes and potasium flouroborate . Roholm (1973) also reported the presence of NaF , MgF 2 , KF, CaF 2 .

10. 10 Anthropogenic sources Industrial Emission Of Fluoride

11. 11 Anthropogenic Sources Industries Other sources are toothpastes, pharmaceuticals, wood preservatives and agrochemicals Result in the emission of gaseous and particulate fluoride into the atmosphere The combustion of coal Phosphate fertilizer and elemental phosphorus Iron and steel manufacture.

12. 12 Fluoride Cycle

13. Deposition Of Pollutant From Atmosphere 13

14. EPA Licensing Of Fluoride Emissions Portland Aluminium has an EPA Licence outlining emission limits for fluoride. Licence limits set out in EPA licences require emissions to be well within safe levels . 14

15. Rate Of Fluoride Deposition Chamberlain (1996) Rate of deposition(µg/m 2 /s) = conc. in air (µg/m 3 ) × deposition velocity (m/s ) The deposition velocity, V g , varies with the form of fluoride (gas or particulate), particle size, wind speed, and the nature of the plant canopy particularly its architecture and wetness. 15

16. Fluoride In Water Dissolve in water and split into ions. Speed of dissolution depend on pH, type of compound. Transport and transformation is influence by pH, hardness and presence of clay. As they travel through the water cycle fluorides usually combine with A luminium . 16

17. Fluoride In Soil F luoride is so strongly adsorbed by the soil that the leaching is slow. The most widespread source of soil contamination arise from the use of phosphate fertilizers . In soils, fluoride is predominantly combined with A luminium or calcium. When the soil is slightly acidic, fluoride tends to adsorb more strongly to soil particles. 17

18. Fluoride In Plants 18

19. Onset symptoms depends on 19 Type and age of plant Concentration Time of exposure Composition of the air Rate of circulation Temperature Type of light and intensity

20. Injury Symptoms The injury starts as a gray or light-green water-soaked lesion, which turns tan to reddish-brown. With continued exposure Necrotic areas increase in size Spreading inward to the midrib on broad leaves Downward on monocot leaves 20

21. 21 Fluoride injury symptoms on leaves of Gladiolus and Douglas fir .

22. Case Studies Effects of fluoride has been studied on Pinus ponderosa by Solberg et al. (1955). Benedict and Breen (1955) have used weeds in evaluating vegetation damage caused by air containing hydrogen fluoride and other air pollutants. Fluoride is reported to cause adverse effects on plant growth and yield. 22

23. Biochemical And Physiological Impacts Of Fluoride Contamination The high internal fluoride concentration disturbs almost all physiological and biochemical process in plants . A number of cellular processes identified to cause deleterious effects on plants disruption of enzymes involved in M etabolic activities P rotein secretion and synthesis G eneration of reactive oxygen species A lteration of gene expression 23

24. At micro molar concentrations At milli molar concentrations 24 Acts as an anabolic reagent Promotes cell proliferation It acts as enzyme inhibitor

25. Fluoride disrupts enzyme activity by binding to functional amino groups that surrounds the enzyme’s active center. Inhibition of protein synthesis and secretion interrupts the signaling pathway involves involved in cell proliferation and apoptosis. Fluoride can increase oxidative stress 25

26. Conclusion Fluoride is a hazardous for both animal and plants. It causes serious damage to the crops grown in the vicinity of fluoride. It effects almost all the biochemical and physiological process of the plant that ultimately led to the reduction in yield. Strict measures should be taken to avoid fluoride contamination. 26

27. References L.H. Weinstein, A.W. Davison; Fluoride in the Environment, CABI publishers, Cambridge, USA, 2004. Greenwood, Delbert A., "Some Effects of Inorganic Fluoride on Plants, Animals, and Man" (1956). USU Faculty Honor Lectures. Paper 41. M. Baunthiyal , S. Ranghara , P. Garhwal ; Physiological And Biochemical Responses Of Plants Under Fluoride Stress: An Overview, Research review Fluoride 47(4)287–293 October-December 2014 . M.N. Ahmad, et al., Hydrogen Fluoride Effects On Local Mung Bean And Maize Cereal Crops From Peri -Urban Brick Kilns In South Asia, Research report Fluoride 47(4)315–319 October-December 2014 . 27

28. S. F. Yang And G. W. Miller, Biochemical Studies on the Effect of Fluoride on Higher Plants, Biochem . J. (1963) 88, 505. P. C. Mishra, S. K. Sahu , A. K. Bhoi , S. C. Mohapatra , Fluoride Uptake and Net Primary Productivity of Selected Crops, Open Journal of Soil Science, 2014, 4, 388-398. Summary & Details: Green Facts, Scientific Facts on fluoride, source document IPCS (2002). 28

29. 29 Thank you!!!

30. 30 Any question???